The primary aim of this proposed research is to examine the social cognitions that mediate and moderate the relations between environmental factors--peers, family, and context--and adolescent drug use and abuse. The theoretical foundation of the project is the prototype/willingness model of adolescent health risk, a modified dual-processing model that presents a social-psychological perspective on health behavior. A core assumption in the model is that adolescents engage in two different types of cognitive processing with regard to health risk and health risk behavior: reasoned and reactive. The prototype model will inform the design and implementation of a series of lab and field studies in which risk-relevant cognitions (e.g., perceived risk, perceived personal vulnerability, social norms, expectancies) and, in some cases, the relation between these cognitions and behavior will be examined. Participants in these studies will include adolescents from age 14 to 21, whose ethnic background is either European American or African American. Particular attention will be paid to person/situation interactions. For example, adolescents'levels of impulsivity (self-control) will be assessed in order to determine if these factors influence the ways in which they think about risk and react to risk opportunity under conditions of high and low stress and/or enhanced affective states. Stressors are diverse and include context (e.g., environmental risk), cognitive load/distraction, and racial discrimination. Consistent with the focus of the prototype model, these studies will target cognitions that are thought to be amenable to modification (e.g., risk images, behavioral willingness), and therefore of potential utility in the design of interventions and preventive-interventions that can help adolescents make healthier decisions about substances. Examining these cognitions and early behavior can provide information about why adolescents use substances and why early use sometimes turns into abuse.